THE CUP OF FLAME.

Put a little newly calcined magnesia into a tea-cup upon the hearth or

hob, and suddenly pour in as much concentrated sulphuric acid as will

cover the magnesia; in an instant, sparks will be thrown out, and the

mixture will become completely ignited. To prevent accidents, the phial

containing the sulphuric acid should be tied to the end of a long stick.

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